Metallurgical furnace.



U. WEDGE.

METALLURGICAL FURNACE.

APPLICATION FILED NOV. 2|, I914- RENEWED APR- 27,1916.

Lmwmw; Patented ]Dec.12,1916.

3 SHEETS-SHEET l- W MQ WEWE U. WEDGE.

METALLURGICAL FURNACE. APPLICATION FILED NOV. 21, 1914. RENEWED APR. 21. 1916.

Patented Dec. 12, 1916.

3 SHEETS-SHEET 3- I "UlLEY WEDGE, @F ARDMOEE, PEWTSYLWANM.

- METALLWQIGM Fllmllthtllh specification of Letters ratent. Patented Deere. t2, llhlllfi.

application filed November at, will, aerial lilo. create. Renewed April 2?, ram. Serial No. admit.

To all whom it may concern:

Be itknown that lLlUrnnr Winner, a citi ten. of the United States, residing in Ardmore, Pennsylvania, have invented certain improvements in Metallurgical l urnaces, of which the following is a specification.

The object of my invention is to supply air to the different chambers of a roasting furnace in such manner that said furnace will be caused to work at its maximum efficiency for sulfur elimination or other onidizing work. This object if attain in the manner hereinafter set forth, reference being had to the accompanying drawings, in which Figure l is a vertical sectional view of a superposed-hearth furnace having four hearths and equipped with a simple form of air supplyingdevice in accordance with my invention, the usual rabble arms being omit ted; Fig.2 is a sectional plan view on the line au, l; 3, 4t, 5 and ti are face views, on an enlarged scale, of the diderent controlling valves in their relation to the air conveying pipes; Fig. 'l' is a vertical sectional view of a furnace having another form of valve control for the air supply; Figs. 8, 9, ill and' ll are, respectively, sectional plan views onthe lines h-t, o--c, o -1d, and c--c, Fig. if Fig. 12 is a vertical sectional view illustrating one method of applying my invention to a furnace in which the air supply is heated by means of the rabble arms, and Figs. l3, it, 15 and 16 are sectional views illustrating the simplest means for controlling the air.

in order to oper te a roasting furnace at its maximum eficiency for sulfur elimination or other oxidizing work the amount of air admitted to each of the progressive hearths of the furnace should be varied, being gradually reduced as the pyrite: or other material which is being roasted passes from hearth to hearth of the furnace, for instance, in a four hearth furnace such as that shown in the drawing the percentage of total air entering the furnace may be distributed as follows: 'llo the top hearth d070, to the second hearth 30%, to the third hearth20%, and to the bottom hearth 10%, or in a furnace in which air is supplied to six hearths the percentage of the total air entering the furnace may be distributed as follows: to the first hearth, 25% to the second hearth,- 20% to the third hearth, 15% to the fourth hearth, 10% to the fifth hearth, and 5% to the sixth hearth, or the respective percentages may be varied so long as there is a progressive diminution in the volume of air supplied to the mass of material passing through the furnace.

Fig. 1 of the accompanying drawings represents a superposed hearth furnace of the type heretofore patented by me but provided with means in accordance with the present invention for supplying graduated volumes of air to the different chambers of the furnace. The furnace shown in the drawings has four hearths 1,2, 3 and at disposed one above another, but it may have .any desired mnnber of hearths, depending upon the character of the furnace and the purpose for which it is to be used.-

The furnace has a central rotating shaft 5 which is intended to carry the usual rabble arms and rabbles whereby the stirring and feeding of the material on the hearths of the furnace is edected, these rabble arms and rabbles, however, not being shown in Fig. has their illustration is not necessary to a proper understanding of my present in vention. H I

The shaft 5 has, at is lower end, a suitably mounted gear wheel whereby it-can be rotated and the hub of this gear wheel forms a water-sealed or otherair tight joint with a casing 6, which is supplied with air by means of an injector l or other suitable device, this air passing up through the hub of the gear wheel and into a pipe 8 centrally disposed within the shaftb and having hollow arms 9 extending therefrom into different chambers of the furnace, these arms conununicating at their inner ends with the interior of the pipe 8 and each discharging at its outer end into the chamber with which it communicates.

The admission of air to the hollow arms 9 is controlled by suitable vertically sliding valves 9 which. determine the 'ed'ective inlet area of each arm, as shown in Figs. 3, 4t, 5

and 6, consequently, assuming that air under pressure is admitted to the pipe '8, such air may be discharged in graduated volumes into the difi'erent chambers of the furnace. The valves 9 have operating rods 9 projecting above the pipe 8, so as to be operated from the outside of the furnace.

in the structure shown in. Figs. 7 -to ll, inclusive, the admission of air to the various arms 9 is controlled by rotary valves 10 adapted to seats on the inner face of the dll lIO

8 and having independent. stems 11 which project above the topof the shaft 5 and are provided with handles 12 whereby any one of the valves 10 maybe conven-- iently and independently turned so as to open, close or adjust the same, and thereby regulate the flow of air through the arms 9, as maybe desired, for the efiective operation of the furnace Y V In some furnaces the air which is supplied to the difierent chambers to efiect oxidation of sulfur elimination is first heated, a common method of thus preheating the air being to pass it through the rabble arms ot-the furnace, and in Fig. 12 I have illustrated the application of my invention to a furnace of thistype. The air passes from the central pipeB through a pipe 13 into the inlet chamber of the rabble arm 14 and discharges from the outlet passage of said arm.

into the shaft 5, and from the interior of the latter passes through the arms9 into the "arious chambers of the furnace, the arms being suitablv valved as at 9 to regulate the volume of air admitted to each chamber. This construction may, however, operate reversely if desired, that is to say, the air may be admitted in the first instance to the hollow shaft 5, may be passed thence to the conducting passages'of the rabble arms and may be delivered by the latterinto the cen' tral pipe 8. fromwhich it is distributedto the various chambers'of the furnace.

. In Figs. 13 to 16 I have shown a means of regulating the volume of air supply. by

' applying to the inner ends of the arms '9 plugs or bushings 15 and providing each of these plugs with an opening of appropriate diameter.

Although I have shown my invention as applied to the ordinary Wedge type of furnace having a series of superposed chambers, it will be evident that it can be applied to a furnace having the chambers otherwise actate 'disposed, or to a furnace having but a sinthe chamber.

I claim: 1. The combination, in a metallurgical furnace, of a casing having a hearth with a treating chamber above the same, a shaft,

an arm projecting therefrom into said treating chamber and open at its shaft end, a valve sliding acrom said open end of the arm but otherwise rigidly mounted, and means for imparting such sliding movement to said valve, said means being otherwise rigid. p

2. The combination, in -a metallurgical furnace, ofa casing having a hearth with treating 'chamher above the same, a tubular shaft having atubular member within the same, a hollow rabble arm having a return passage therein which communicates at one end with the interior of the tubular shaft and atthe other end with the interior of the tubular member within the shaft, an air distributing arm projecting into the pendent of the rabble arm, said air distributmg arm communicating with but one .of said tubular members, means for sup- I UTLEY WEDGE. v Witnesses KATE A. BEAnLn, HAMILTON D. Tonnes.

working chamber of the furnace but inde- 

